When his fever spiked, he thought someone was setting him on fire. When orderlies slid him into an MRI, he thought he was being fed into an oven. Frequent catheter changes seemed like sexual abuse. Dialysis? He thought someone was taking blood out of a dead woman's body and injecting it into his veins.

The horrifying, violent hallucinations plagued David Jones, now 39, during a six-week stay in the intensive care unit at Chicago's Northwestern Memorial Hospital — and for months after he was discharged. He thought he was going crazy and felt very alone.

He wasn't.

Recognizing the prevalence of the problem, doctors and nurses across the country are now pushing an ambitious campaign to change practices in intensive care units to reduce cases of "ICU delirium" — a sudden and intense confusion that can include hallucinations, delusions, and paranoia.

Anywhere from a third to more than 80 percent of ICU patients suffer from delirium during their hospital stay. And one-quarter of all ICU patients suffer from post-traumatic stress disorder once they leave, a rate that's comparable to PTSD diagnoses among combat veterans and rape victims. Patients with ICU delirium are less likely to survive and more likely to suffer long-term cognitive damage if they do.

"This is a massive, massive public health problem," said Dr. Wes Ely, a pulmonologist and professor of medicine and critical care at Vanderbilt University Medical Center in Nashville, Tenn., who was among the first to recognize the scope of the problem.

Ely is pushing his colleagues in ICUs across the country to reduce the use of sedatives and ventilators and push patients to get on their feet as soon as possible, in a bid to minimize delirium. The talks he gives to highlight the issue show patients talking and texting while on ventilators — a major break from the traditional practice of heavily sedating them. He also shows patients walking through hospital halls despite grievous injuries.

The "ICU Liberation Campaign," which Ely cochairs, is organized by the Society for Critical Care Medicine, a professional group for ICU clinicians. If it works, it'll both improve patient outcomes and lower hospital costs.

But it's been a hard sell.

Despite its heavy clinical toll, ICU delirium is often ignored. Intensive care units are so stressful, so noisy, and so fast-paced that delirium is often overlooked.

"You may have one patient going into shock while another needs to be reintubated, so people get busy," said Dr. Matt Aldrich, an anesthesiologist who has been implementing the ICU Liberation Campaign at the University of California, San Francisco, Medical Center, where he directs adult critical care. "Delirium has definitely taken a backseat."

It's not that clinicians don't believe in the protocols, Aldrich said. It's just hard to make time to implement them. "The challenge is to slow yourself down and do the things you need to be doing. It's daily work. It's maintenance," he said. "It's not letting little things slide and falling into old patterns."

Keeping patients alive — but at a cost

In a way, ICU delirium is a problem born of success: Today's intensive care units keep alive patients who would not have survived 20, 10, or even five years ago. ICUs have come so far in curbing problems like sepsis and acute respiratory distress syndrome that they've created a huge population of "ICU survivors" — those who make it out alive but end up severely impacted mentally and psychologically.

"We used to call it ICU psychosis," said Justin DiLibero, a clinical nurse specialist working to reduce ICU delirium in the neuro and surgical ICUs at Beth Israel Deaconess Medical Center in Boston. "We knew it was common but thought patients got better when they got home. Now we know they come into the hospital as one person and leave as someone else."

Family members are often the first to see that their loved ones "aren't themselves." Patients may act paranoid, lash out in anger, or simply seem quite silly, for example planning large galas while still intubated.

While the exact causes of ICU delirium are not fully understood, risk factors seem to include ventilation, which can reduce the flow of oxygen to the brain, and heavy sedation, especially with benzodiazepines, which can have neurotoxic effects. Immobility and physical restraints appear to contribute to psychological distress as well. The lack of sleep, noisy alarms, constant prodding by nurses and doctors, and patients' inability to keep their hearing aids and glasses on may contribute, too.

The effects can linger long after discharge.

"As soon as I got home there were cognitive issues, really bad panic issues, flashbacks, all very gruesome," said Jones. "I felt like I'd endured months of torture. I was scared to go to sleep. I'd wake up in a cold sweat."

Jones had entered the hospital in 2012 with stomach pains that turned out to be caused by acute necrotizing pancreatitis. His pancreas was literally digesting itself; then his other organs started to fail. He was put on life support: On a respirator and dialysis, fed through a tube, the stocky and athletic Jones lost 70 of his 260 pounds. Nine days into his hospital stay, doctors gathered his family to say goodbye.

Thanks to surgery, a flood of antibiotics, and dedicated hospital staff, Jones survived. He's incredibly thankful for the care he received.

But he's also angry, now that he knows how widespread ICU delirium is, that not a single person talked to him or his family about the mental and psychological issues that so many ICU patients face.

"I thought, 'Why in the world is this not included in post-discharge instructions?'" Jones said in a telephone interview from Chicago, where he has returned to work as a legal analyst. "They were so happy they had saved my life. But no one told me to expect any of this."

A culture of 'protecting' patients with sedation

Ely has always been proud of the work done at his ICU. But in the late '90s, he started to notice something deeply unsettling: Many of his patients weren't doing well after they left the hospital. Some were severely impaired. Many couldn't return to work.

"They couldn't find their cars or balance their checkbooks," he said. "We wondered, 'What happened to them in the ICU? What went wrong?'"

Ely was shaken by the encounters, but when he tried to bring up the issue with fellow intensive care physicians, or critical care specialists, or even with the National Institutes of Health, he got no traction.

His call to ease up on restraining and sedating patients butted up against what Ely says was a deeply entrenched — and deeply paternalistic — ICU culture. "The idea has long been: 'We want to keep you unconscious so you don't suffer.'" Ely said. "We thought we were 'protecting' patients."

There were practical issues too: Heavily sedated patients are far easier for nurses to work with than patients who are frightened, agitated, or in pain. And it can be very hard to detect delirium in patients who are lethargic and seem unaware — but may still be delusional and suffering. "They told me I was in a coma," Jones said. "But I was aware."

Ely has spent the past two decades studying the issue and amassing the kind of data that are starting to convince his colleagues. A 2013 study, for example, showed nearly 75 percent of ICU patients developed delirium during their hospital stay. In roughly one-third of those cases, their cognitive problems were so severe that even one year after discharge, they mimicked mild traumatic brain injury.

To minimize such damage, Ely developed a protocol dubbed ABCDEF, with steps such as assess for delirium, choose sedation wisely, and push patients to early mobility.

When the procedures are implemented, they seem to work wonders.

At Beth Israel Deaconess Medical Center, care teams in the medical ICUs have reduced the number of delirious patients by 60 percent since 2012, at a cost savings of thousands per patient. They did this by carefully assessing patients for delirium, making sure multiple care team members agreed on those assessments, and then reducing sedation and particularly benzodiazepine use whenever possible.

"We discussed every patient every day, and delirium was part of the discussion," said DiLibero, the nurse specialist who ran the project, which was funded by the American Association of Critical-Care Nurses, which recently issued a practice alert about delirium to its members. When nurses weren't sure what to do, DiLibero said, they could call in "nurse champions," who act as mentors and leaders.

Looking for delirium is especially important in elderly patients. Without a careful assessment, elderly patients with delirium may be misdiagnosed with dementia and sent to nursing homes unnecessarily.

The project at Beth Israel worked so well, it's been adopted by other ICUs at other regional hospitals. But it wasn't easy to get there. DiLibero has been working on the issue since 2010, his commitment sparked by seeing so many ICU patients, including his own grandmother, succumb to delirium.

"It's taken years of concerted effort to get to this point," he said. "It's been about changing a culture." That change is now palpable in his unit.

"When I started in ICU, anyone who was going to be intubated, they'd all be sedated, pretty deeply sedated," DiLibero said. "Now some patients are completely off sedatives while still on a ventilator. I never thought I'd see that."

While there is agreement that it's crucial to prevent delirium whenever possible, many questions still remain on how best to treat it after it occurs. Vanderbilt is one of the few hospitals that offers a post-ICU treatment center; opened in 2012, it draws patients from around the country. At the center, patients are treated by a team that includes an ICU physician, nurse, pharmacist, case manager, and neuropsychologist who work together to help patients understand and alleviate symptoms.

Jones said therapy in Chicago was a great help to him, and included revisiting his ICU room to better understand his hallucinations.

He's also committed to talking publicly about his experience in hopes others won't suffer as he did. And he always carries a carefully worded life directive in his briefcase that makes clear that any intensive treatment he might need is provided in a way that is less likely to cause delirium.

"As bad as my illness was," he said, "the post-ICU was more traumatic."

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